I'm glad you liked my ideas. This mod excites me. It will add such a great layer of depth to the magic system! Can't wait to see how you tweak the game models to actually implement all these creatures. FE is lucky to have such talented modders.

-thorns Immoblize unit for 2 turns. Thorns life leach x HP per turn returning leached life back to the caster.

I'll have to modify it to fit spell mechanics.

Vampiric Snake - Each time it hits an enemy in melee, it gains +1 Leeched Health. By using 3 Leeched Health, the snake may Heal a friendly champion. By using 5 Leeched Health, the Vampiric Snake explodes, killing itself, but casts Heal on all friendly units.

Enchant Blood Thrall - the caster plucks up a random peasant and infuses them with death magic to make them utterly loyal. The potent magic in their blood is unleashed when spilled for the benefit of the caster or other allies.

Ability - potent heal spell that either kills or seriously wounds the blood thrall, essentially making them a bipedal health pack

Add an odd hue to a peasant model and your good. For added coolness, make the spell require a city as target and drop the population by 1 on summoning.

Conjure Celestial - strange magical constructs reminiscent of elementals but forged of obscure star-magics, Celestials are deadly in combat not only for their skill in battle but because to strike them with a weapon is to risk setting loose strange energies.

Ability - maybe a Starfall ability that is essentially a direct damage spell. Passive ability - "chaos" spell or equivalent applied to attackers with a % chance depending on celestial's power (if you wanted lesser/greater versions)

Quoting mqpiffle, reply 21Summon Wisp (or Will o' Wisp) : When adjacent to any enemy, that enemy has a 50% to become enthralled and lose its next turn. Att: 0, Def: 0, Dodge: Something High, HP: 50 -ish

Doesn't work with the mechanics. What we can do is trigger stuff when attacked, or when attacking. But we already have summons doing stuns on attack and defense.

I like the creature though. I will think of something.

Can you set it up such that it can only be summoned within 1 tile of target enemy, and as such it acts like a flanker so adjacent units can only move 1 tile per round. Maybe it casts a spell which slightly reduces initiative or accuracy for the next round as well? Just some thoughts...